This invention relates generally to singulation detection, and, more particularly to a system to reliably detect if parcels are singulated.
In the past, parcels, such as packages traveling through the U.S. mail, were transported by a single conveyor belt to an automatic sorter. Each parcel could be labeled with a machine-readable bar code sticker, for example, but in the systems of the past, an attendant would have to orient the parcel so that the label could be detected and read by the sorter. To complicate the systems, often parcels were delivered to the sorter in bunches, making them difficult to handle and sometimes creating jams. Manual intervention would be required to perform a process known as singulation, or separation of the parcels from each other, to enable the automatic sorter to operate correctly so that the parcels could be properly distributed. Due to the non-uniform shape and size of parcels, this effort was time-consuming and cumbersome to the operating attendant.
Automated package delivery systems such as mail processing systems now include automatic parcel singulation systems. These systems usually separate parcels, bundles, and other packages one from another to prepare them for automated distribution. But when the parcels are stacked or lying too close together, an automated system cannot always reliably singulate the parcels for proper sorting because a group of parcels can be seen as one parcel by the automatic system.
Machines that address the problem of reliable singulation can include a singulator, a side-by-side remover, a flow controller, and a recirculating conveyer. In this type of equipment, parcels enter the singulator through an infeed and are driven to one side by skewed rollers. Successive belts increase in speed and create spaces between the packages. The skewed rollers align the packages to one side of the unit to form a straight line. A typical side-by-side remover transports downstream any packages of the width of the narrowest package while deviating other packages to be recirculated back onto the singulator. In some systems, the side-by-side remover is augmented by an optical recognition system that detects “piggy-back” items. Packages that are transported downstream enter a flow controller that meters the rate of packages that it discharges by inserting gaps between packages. Doubles and overflow packages are pulled off the flow controller belt and recirculated to the infeed of the singulator by the recirculating conveyor. Sometimes these automated systems use dimensioning equipment which automatically measures the external characteristics of parcels as they move along a conveyor.
The current systems are deficient, however, when it comes to reliably identifying improperly singulated articles. What is needed is a system that decreases the likelihood that parcels are determined to be singulated when in fact they are not.